Caffeine consumption and disability: clinical issues in rehabilitation.

The consumption of caffeine may at first seem to be of minor importance when compared to the many variables which influence the lives of rehabilitation clients. However, abuse of caffeine in our society is so common that its effects are often overlooked or disregarded. Rehabilitation professionals who have a responsibility to plan holistic and comprehensive rehabilitative services should consider the potential impact of caffeine abuse. In simple terms, ingestion of too much caffeine can have negative consequences on the health and well-being of the rehabilitation client.

Accordingly, caffeine abuse can undermine rehabilitation planning, can exacerbate existing disabling conditions, and can generate new symptoms which may lead to misdiagnoses. This article describes the life-impact that caffeine can have on human beings, specifically those with disabilities. The article seeks to explain the need for rehabilitation counselors and other professionals to evaluate clients' caffeine intake to determine the effects it may have on rehabilitation outcomes. Toward that goal, the impact caffeine use can have upon the accuracy of professional assessment and evaluation of the client's life-situation should be taken into account. Conclusions from such evaluations form the basis for subsequent rehabilitation planning and services. To a large degree, the success of the entire rehabilitation process may be governed by the accuracy of such evaluations.

Pharmacological Aspects

As a chemical, caffeine is a methylated xanthine, a powerful central nervous system (CNS) stimulant which can arouse all levels of the brain and the skeletal muscles (American Pharmaceutical Association, 1979; Liska, 1986; Ray & Ksir, 1990). Within thirty minutes after ingestion, caffeine peaks in blood levels and affects the CNS. It reaches its maximum effect in two hours. Caffeine has a half-life of approximately three hours; less than ten percent leaves the body unchanged (Ray & Ksir, 1990).

A regular cup of coffee may contain as much as 150 mg of caffeine, while soft drinks generally contain about half that per can. About 200 mg of caffeine will activate the cortex, cause an arousal pattern on an electroencephalogram (Liska, 1986; Ray & Ksir, 1990), and decrease fatigue and drowsiness (Ray & Ksir, 1990). A dosage of five to six hundred mg of caffeine a day presents a significant health risk (James & Stirling, 1983). Such pharmacological action may exacerbate disabling conditions which can lead clients and professionals alike to confuse new symptoms from this drug use with symptoms of disability.

Although caffeine dilates coronary arteries and increases peripheral circulation, it constricts blood vessels in the brain (Liska, 1986). Ironically, the subjective experience of such physiological changes may encourage some individuals to self-medicate with caffeine as a way of coping with the adverse physical effects. In reality, however, this self-medicating may only serve to perpetuate or worsen the physical impact of abuse.

Caffeine stimulates the muscles of the heart (Liska, 1986; Ray & Ksir, 1990) and can cause palpitations and tachycardia (Victor, Lubetsky, & Greden, 1981). Excessive use can cause premature ventricular contractions (Greden, 1974; Greden, Victor, Fontaine, & Lubetsy, 1980). Caffeine can render antihypertensive medications ineffective (Lane, 1983) because it increases blood pressure (Lane, 1983; Liska, 1986; Ratliff-Crain, O'Keeffe, & Baum, 1989). Rehabilitation counselors, therefore, should be particularly alert for caffeine abuse in clients suffering from cardiovascular disorders or essential hypertension.

It has not been fully determined if caffeine precipitates coronary heart disease. LaCroix, Mead, Liang, Thomas, and Pearson (1986) predicted that men (non-smokers) who are heavy coffee drinkers have a two to three times greater risk of developing coronary disease because of their caffeine intake. They also note a strong association between coffee consumption and how much an individual smokes. The amount of caffeine an individual consumes five to ten years prior to the onset of coronary disease may not be as closely associated with the development of the disease as the amount consumed directly prior to its manifestation (Victor, Lubetsky, & Greden, 1981). However, Liska (1986) denied that caffeine consumption increases the risk of coronary heart disease, while Lane (1983) speculated that caffeine affects the development of coronary heart disease only in individuals undergoing continuing stress. Rehabilitation clients with a variety of conditions may experience such continual stress and may, therefore, be more susceptible to eventual heart problems.

Caffeine dilates the bronchial tubes (Liska, 1986) and increases respiration levels (Liska, 1986; Ray & Ksir, 1990) by stimulating the medulla respiratory center (Victor, Lubetsky, & Greden, 1981). Traditional wisdom suggests that coffee can bring immediate relief in some instances of asthma attack. This increase in respiratory activity may be important to rehabilitation clients who work in environments in which air contaminants are present. These clients may drink coffee to improve respiration, but may thereby inhale more easily the contaminants.

In the gastrointestinal system, caffeine increases gastric irritation and digestive juice secretion (Liska, 1986). The risk of developing pancreatic cancer is greater for a caffeine consumer than for a noncaffeine consumer (MacMahom, Yen, Trichopoulos, Warren, & Nardi, 1981). Caffeine's effects on the genitourinary system include diuresis (Liska, 1986; Victor, Lubetsky, & Greden, 1981) because it inhibits renal absorption of sodium (Snyder & Sklar, 1984), and diarrhea (Victor, Lubetsky, & Greden, 1981). Caffeine increases the work capacity of muscles (Liska, 1986) and may slightly raise basal metabolic rates (Ray & Ksir, 1990; The United States Pharmacopeial Convention, Inc., 1987). Caffeine use may also cause tremors and shakiness (Liska, 1986), producing visible symptoms which may distort authentic symptoms of disabling conditions.

Women who consume caffeine have greater difficulty becoming pregnant (Wilcox, Weinberg, & Baird, 1988). The FDA cautions pregnant women and nursing mothers to avoid caffeine as it may be harmful to the embryo during the first trimester (Liska, 1986). Caffeine ingested by the mother can be passed to a nursing infant through breast milk. In an infant, caffeine may cause abdominal pain, fast heartbeat, nervousness, severe jitters, or whole-body tremors, and vomiting (The United States Pharmacopeial Convention, Inc., 1987).

Caffeine and Mental Illness

The consumption of caffeine among people with psychiatric disabilities is roughly double that of the general population (Furlong, 1975). There is a direct association between moderate and high caffeine intake and the presence of various psychiatric symptoms (Wells, 1984; Greden, 1974). Thus, the possibility of incorrect diagnoses should be considered (James & Stirling, 1983). The DSM III-R (American Psychiatric Association, 1987, p. 138) warns that manic episodes, panic disorders, and generalized anxiety disorders may resemble caffeine intoxication. Caffeinism's resemblance to panic disorder (National Institute of Mental Health, 1985, as cited in Ray & Ksir, 1990, p. 232), anxiety neurosis (American Pharmacuetical Association, 1979; Hire, 1978; Greden, 1974), and personality disorder (Furlong, 1975) have been documented. Excessive caffeine use has precipitated delirium, and chronic and acute anxiety in psychiatric patients. Upon cessation or reduction of caffeine intake, symptoms abated (Stillner, Popkin, & Pierce, 1978; Greden, 1974; Mikkelsen, 1978; Winstead, 1976), suggesting that clinically significant levels of anxiety and tension states can be reversed by decreasing caffeine intake (DeFreitas & Schwartz, 1979).

Caffeine's role in psychiatric health not only influences diagnoses, it also affects the pharmacological action of psychotropic drugs and their uses. Abusers of caffeine are likely to be treated with phenothiazines or antidepressants (Winstead, 1976); higher doses of phenothiazines may be prescribed due to the clinician's failure to recognize caffeine's ability to increase catecholamine output (Greden, Fontaine, Lubetsky, & Chamberline, 1978) and observable initial agitation or excitement (Shisslak, Beutler, Scheiber, Gaines, La Wall, & Crago, 1985). The combination of caffeine and oral phenothiazine can create additional symptoms. A 30-year-old female reported feeling "strange" and experiencing paranoid thinking, both of which ceased in the absence of caffeine. These symptoms did not recur with caffeine use after the patient was stabilized on phenothiazines (Mikkelsen, 1978).

The tranquilizing effects of benzodiazephine, a frequently used minor tranquilizer (Tallman, Paul, Skolick, & Gallager, 1980), are countered by caffeine. Therefore, higher doses are likely to be prescribed even though the preferred treatment is caffeine elimination (Greden, Procter, & Victor, 1981). The reduction of caffeine intake resulted in marked improvement in a patient who had previously been unsuccessfully treated for

severe anxiety with minor tranquilizers and other psychoactive agents (Molde, 1975).

Caffeine use renders more toxic or less effective monoamine oxidase inhibitors (MAOI) and lithium salts used to treat some mood disorders (Neil, Himmelhock, Mallinger, Mallinger, & Hanin, 1978). In two cases of bipolar disorder in which patients were treated with 450 mg controlled-release lithium and 1500 mg lithium on divided doses, respectively, discontinued coffee use resulted in increased tremors until lithium doses were lowered. Such cases suggest that higher-than-normal doses of lithium are needed to produce therapeutic serum levels when high caffeine intake is present (Jefferson, 1988).

The therapeutic implications of caffeine use associated with an individual's attempt to counteract the effects of a specific medicine need to be considered. People with schizophrenia who are treated with phenothizianes and tricyclic antidepressants may use caffeine to counter the dry-mouth side-effect (Winstead, 1976) and unpleasant sedative effects (Neil, Himmelhock, Mallinger, Mallinger, & Hanin, 1978; Winstead, 1976). Despite such reports, Koczapski, Paredes, Kogan, Ledwidge, and Higenbottam (1989) stated that caffeine reduction is not clinically necessary for patients on high doses of neuropleptics. In any instance, however, caffeine is a poor choice of beverage for people with psychoses because of increased anxiety levels (Winstead, 1976). People with mood disorders who are medicated with tricyclic antidepressants and MAOI may use caffeine to counteract the dysphoria associated with decrements in performance and diminished energy level. If caffeine intake is lowered or eliminated, a return to previous patterns of retarded, hypersomnic depressive states follows. Anxiety, irritability, and non-purposeful psychomotor agitation are significantly reduced (Neil, Himmelhock, Mallinger, Mallinger, & Hanin, 1978).

Caffeine adds to the complexity of rehabilitation for clients with severe and persistent mental illness in many ways. In vocational rehabilitation (VR), for example, the process of determining eligibility may be more difficult if the client abuses caffeine. The counselor may be unable to distinguish among the symptoms of the illness, the effects of caffeine, and the influence of medication whose pharmacological action has been altered by caffeine. Additionally, reasonable expectation for a VR client with mental illness may be more difficult to determine if the effects of caffeine have "contaminated" evaluative data concerning the primary disability. In such circumstances, caffeine may effectively undermine established rehabilitation practices related to diagnostic studies. In other words, the effects of caffeine may invalidate to some degree all information about a client's condition and vocational potential.

Psychosocial Impact

Caffeine use is an acceptable social pastime. The positive social implications attributed to caffeine consumption include its usefulness as a stimulant and as a "relief." Such motives for consumption are the best predictors of likely caffeine abuse (Graham, 1988). Society encourages the use of coffee and ignores symptoms of its abuse as "coffee nerves." Many people "treat" these symptoms by rationing their morning intake of coffee (Greden, 1974) or by switching to decaffeinated coffee. An individual can become psychologically dependent on caffeine (Furlong, 1975; Griffiths, Bigelow, & Liebson, 1986; Griffiths, Bigelow, & Leibson, 1989; Ray & Ksir, 1990; Winstead, 1976) when he or she experiences positive effects after caffeine intake (Griffiths, Bigelow, & Liebson, 1986). If caffeine is withheld from a regular high user of caffeine, the individual may experience substantial adverse disruptions in mood and behavior (Griffiths, Bigelow, & Liebson, 1986).

Caffeine use may affect an individual's score on the State-Trait Anxiety Index and the Beck Depression Scale. Some psychiatric patients who were moderate to high consumers of caffeine have had elevated state anxiety scores (Greden, Fontaine, Lubetsky, & Chamberline, 1978; Winstead, 1976). These patients indicated feeling tired, blue, like crying, and in a state of tension over recent concerns more often. They indicated feeling pleasant, rested, happy, or content less often (Greden, Fontaine, Lubetsky, & Chamberline, 1978).

Caffeine withdrawal headaches are an indicator of caffeine dependence (Ray & Ksir, 1990). Patients at the University of Michigan Medical Center who had experienced such headaches had significantly higher trait and state anxiety scores than patients who had not experienced withdrawal headaches (Greden, Victor, Fontaine, & Lubestsky, 1980). Non-psychiatric individuals who ingested highly caffeinated coffee (400 mg) and were placed in a stressful situation showed a three-fold increase in state anxiety in comparison to a similar group consuming the same high caffeine level but being placed in a low stress situation (Shanahan & Hughes, 1986).

Trait anxiety reflects how one generally feels. Trait anxiety scores in psychiatric patients who were moderate to high consumers of caffeine were elevated. The patients reported feeling more anxious, nervous, and upset and less calm and joyful (Greden, Fontaine, Lubetsky, & Chamberline, 1978). However, Winstead (1976) found the trait anxiety scores for psychiatric patients who were high users of caffeine the same as those of psychiatric patients not considered to be high users of caffeine. Still, psychiatric patients who were high consumers of caffeine have had elevated Beck Depression scales (Greden, Fontaine, Lubetsky, & Chamberline, 1978). Patients who had experienced headaches had elevated scores, especially on items assessing sadness, guilt, pessimism, failure, and expectation of punishment (Greden, Victor, Fontaine, & Lubetsky, 1980).

An individual may resume caffeine consumption to alleviate the physical distress of withdrawal headaches (Greden, Victor, Fontaine, & Lubetsky, 1980). Ironically, heavy caffeine users who also use minor tranquilizers may ingest additional caffeine in an attempt to counteract the toxic effects of their regular high caffeine consumption (Greden, Procter, & Victor, 1981). Deprivation produces stress-like withdrawal symptoms independent of other events (Ratliff-Crain, O'Keeffe, & Baum, 1989).

Caffeine's effect on performance is individualized (Revelle, Amaral, & Turriff, 1976). It may counteract decrements in simple vigilance task performance caused by fatigue (Elkins, et al., 1981). It may also increase auditory vigilance and visual reaction time (Liberman, Wurtman, Emde, Roberts, & Coviella, 1987). Caffeine does, however, have a negative effect on free recall and increases motor restlessness (Elkins, et al., 1981). While caffeine abusers may feel an increased level of alertness after consuming caffeine, such increases may not be accompanied by changes in objectively measured performance (Murray, 1988). For some people with disabilities, this phenomenon may reflect at least the potential for miscalculating their own level of functioning in job skills testing. Counselors should be alert to such differences in performance as a possible indicator of caffeine abuse.

Caffeine may also increase the effects of performance-induced stress (Shanahan & Hughes, 1986). Stress increases the demand for coffee in habitual users to the extent that they need caffeine to perform at the same level at which they would perform if they had never started using coffee. Stress aggravates the perceived need for caffeine, whether the person is deprived of it or not (Ratliff-Crain, O'Keeffe, & Baum, 1989). Again, rehabilitation counselors and other professionals should recognize that the stress related to disability and to rehabilitation itself may trigger in some clients the perceived need for even more caffeine when their performances are to be measured.

Tolerance for caffeine may develop with regular consumption of large quantities (usually exceeding 500-600 mg per day), but this tolerance may be overridden when the dosage is increased (Victor, Lubestky, & Greden, 1981). High consumers may view caffeine as causing headaches, anxiety, confused thinking, and slowness in movement. They also may view it as relieving headaches, calming nerves, enabling clearer thinking, giving energy, and making one feel less depressed (Greden, Victor, Fountaine, & Lubetsky, 1980). Caffeine's constriction of brain vessels does relieve hypertensive headache (Ray & Ksir, 1990) when coupled with ergot (Liska, 1986).

The social acceptability of caffeine facilitates its use as a substance for self-medication. Clients recovering from alcohol abuse may drink large quantities of non-alcoholic beverages, including those containing caffeine (Stockwell & Town, 1989) which may lead to increased arousal and agitation (Miller, 1989). Along similar lines, one of the current authors (Holmes) believes there is sufficient anecdotal evidence to suggest that some individuals suffering from chronic pain may use high dosages of caffeine as an "indirect" analgesic. The stimulating effects of caffeine may serve to "boost" the individual's activity level despite continual pain. If such behavior is common, it could interfere with long-term employment. Although a client suffering from chronic pain might improve functional abilities at specific points in time, increased caffeine tolerance might eventually erode his or her ability to "control" pain in a routine work setting.

Caffeine abusers are also more likely to use minor tranquilizers (Greden, Procter, & Victor, 1981; Greden, Fontaine, Lubetsky, & Chamberline, 1978), sedative-hypnotics, ethonal (Greden, Fontaine, Lubetsky, & Chamberline, 1978), and cigarettes (Greden, Fontaine, Lubetsky, & Chamberline, 1978; Greden, Procter, & Victor, 1981; Gilliland, & Andress, 1981). An increase in caffeine use corresponds to an increase in smoking habits (Greden, Procter, & Victor, 1981; Gilliland & Andress, 1981). Winstead (1976) noted that among psychiatric patients there is a specific desire to seek out caffeine. Psychiatric patients who abuse caffeine are more likely to be older, single, divorced, or separated. There is a higher incidence of psychosis and a lower incidence of depressive neurosis among psychiatric patients who abuse caffeine (Winstead, 1976). Heavy caffeine users seem to be intrinsically less sensitive to its adverse effects while responding more to its positive actions (Snyder & Sklar, 1984).

Just as the effects of caffeine may be personal and idiosyncratic, some differences may be linked to gender. Part of this difference may be attributable to sociopolitical issues. Greden, Victor, Fontaine, and Lubetsky (1980), for example, suggested that women may abuse caffeine because clinicians are more likely to prescribe sedatives, stimulants, and tranquilizers to them. One study suggested that psychic stress among women increases with increased caffeine consumption (Vener & Krupka, 1982). Other researchers have suggested that caffeine may reduce the efficiency with which women rehearse information in working memory (Erikson, et al., 1984).

Implications and Recommendations

Rehabilitation counselors have an ethical responsibility to do "all that can be done" for clients and to strive for total rehabilitation outcomes (Wright, Leahy, and Shapson, 1987, p. 107). Additionally, rehabilitation counselors are expected to approach the rehabilitation process and the client with a holistic perspective (Goodwin, 1986) so that the client's life situation can be assessed completely. An advantage of a holistic health approach is that it allows the professional to consider such things as caffeine consumption as a factor in mental distress (Martin and Martin, 1982). Although caffeine as a "food product" has been linked to cancer (Grady & Siwolop, 1984) caffeine users may still not actively seek information about caffeine (Johnson-Greene, Fatis, Sonneck, & Shawchuck, 1988). For these reasons, caffeine consumption and abuse must be evaluated according to the impact they have upon the client's life in general and according to the impact they have or might have upon the rehabilitation process or plan. In a general sense, rehabilitation counselors should routinely seek information from clients about their caffeine consumption levels. Such information should be comprehensive enough to allow the counselor to detect patterns of consumption over time, not sporadic episodes of situational abuse. Toward that goal, counselors need to ask such questions as the following:

1. How many cups of regular coffee does the client consume

daily? 2. Does the client consume other beverages, foods, or

medicines containing caffeine on a regular basis? 3. Does caffeine consumption figure prominently in the

client's social life? 4. Does the client use or plan to use high dosages of caffeine

in a work setting? 5. Given the level of routine caffeine ingestion, what

symptoms are likely to occur in the client? 6. If the client clearly abuses caffeine, what physical,

social, or psychological effects might arise from reduced

consumption? 7. What psychological "states" are likely to be exacerbated,

created, or masked by the consumption? 8. Is the client's use or abuse of caffeine intertwined

with any other behaviors likely to create health problems

(e.g., smoking)? 9. Does the client's consumption level reflect important,

routine family behaviors or interactional rituals? 10. Does the client recognize that caffeine abuse constitutes

a potentially serious problem for which he or

she must take responsibility to change?

When the effects of caffeine consumption are evaluated for total life impact, the social implications should not be de-emphasized. A client with a disability may be socially isolated. Opportunities for social interaction through such a common activity as "having coffee" with friends may represent an important and vital part of the client's life. He or she may be unwilling to sacrifice such opportunities for the sake of improving general health through reduced consumption. Researchers in one study suggested a strong relationship between extroversion and caffeine use (Landrum & Meliska, 1985), a connection which complicates social use of caffeine.

As clients get older their social networks may become smaller while disability itself may serve to alienate clients from pre-existing contacts (Wesolowski, 1987). Rehabilitation counselors need to weigh carefully the important role that social interaction plays in the client's life. The value of social interaction may, in fact, be greater than the need to reduce caffeine consumption, at least in the immediate sense. By encouraging gradual reduction of consumption or the switch to decaffeinated beverages, the rehabilitation counselor can help a client move from abuse to use without reducing social contact with others.

The social implications of caffeine use and abuse spread to the world of work as well. The rehabilitation counselor should recognize that caffeine abuse can influence the results of vocational evaluation, on-the-job behaviors, job performance, and relationships with co-workers. Counselors should investigate the following issues related to caffeine abuse and vocational success:

1. How will the client's consumption of caffeine influence

safety and productivity on a given job? 2. In terms of job performance, how will caffeine interact

with any medication or pre-existing symptoms? 3. Are some work settings more likely to encourage increased

caffeine consumption? 4. Are co-workers likely to affect or to be affected by

the client's level of caffeine consumption in the social

sense? 5. Will the stimulating effects of caffeine adversely affect

the client's ability to follow directions or to react

to supervision? 6. Will a particular job setting tend to decrease the client's

usual level of caffeine consumption so as to induce

withdrawal symptoms? 7. Does the client abuse caffeine in an attempt to self-medicate

a condition which should be treated with

prescription medication?

Counselors should take special note of the fact that switching to decaffeinated coffee may not be the simple solution it seems. For one thing, decaffeinated coffee may not be available in many work settings, particularly those in which managers prefer workers to consume caffeine as a method assumed to boost production. Even some inpatient treatment or rehabilitation programs may make regular, but not decaffeinated, coffee available to clients. In social settings, decaffeinated coffee or beverages may be equally unavailable; the client's friends and family members who constitute primary social support may prefer to keep on hand only those drinks containing caffeine.

Coffee is generally decaffeinated with solvents which some people may fear for health reasons. Some processors use water and charcoal filters instead of solvents, both of which may add to the retail price of the coffee (Consumers Union, 1991). A client who does attempt to change to decaffeinated coffee may revert to use of caffeine when he or she begins to experience the withdrawal symptoms mentioned earlier.

Conclusion

This review of caffeine use and abuse is not meant to make more of the subject than is warranted. However, even if our society condones and encourages caffeine use while "allowing" caffeine abuse, rehabilitation clients may be particularly susceptible to caffeine's worst effects. The process of rehabilitation is stressful on clients (Goodwin, 1980) and may require their best efforts. Like many substances, caffeine may be viewed as beneficial and harmful at the same time. Thus it remains for the rehabilitation counselor to determine the impact of caffeine on any particular client.

From a professional point of view, the counselor needs information about caffeine usage before he or she can anticipate any problems usage might have on eventual rehabilitation outcomes. Beyond this, however, such information can alert the counselor to likely problems related to assessment and evaluation of a disabling condition, vocational potential, and psychological well-being of the client. High levels of caffeine consumption can "cloud" the quality of conclusions about the impact disability actually has on a client's life.

Caffeine abuse can also influence the quality of the client's subjective experience of disability and his or her ability to provide the counselor with accurate information. As a stimulant, caffeine may hide some symptoms and create others which can confuse the counselor. The professional rehabilitation counselor who investigates the client's normal use of caffeine and of products containing caffeine does so as a way of fulfilling his or her professional and ethical responsibilities to the client. That such information is included in the evaluation of the client's overall life situation will mean that rehabilitation planning and services have a better chance of helping the client achieve his or her goal of employment or independence.

Ms. Ochs is a graduate in the Rehabilitation Counseling program at Emporia State University. Mr. Holmes is an instructor in the Rehabilitation Counseling program and Dr. Karst is the coordinator of the Rehabilitation Services Education program in The Teachers College, Emporia State University, Emporia, Kansas 66801.

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